Meanings of contained a promise in English

This picture contained a promise of a different sort.

With a sign of the head and a smile that contained a promise she intimated to them that they were dismissed.

The Chefoo Convention, closing the Yunnan incident, contained a promise from the Chinese government to allow an English mission to pass through Tibet.

She turned her eyes to her husband as if to persuade herself that that harsh face contained a promise of mercy, dearly brought.

I am not unwilling to believe what is said of it, that it contained a promise of the powers which its author afterwards put forth.